A Comprehensive Analysis of the Entire Die-Casting Production Process: How Mold Design, Die-Casting Technology, and Post-Processing Affect Product Quality

A Comprehensive Analysis of the Entire Die-Casting Production Process: How Mold Design, Die-Casting Technology, and Post-Processing Affect Product Quality

Quality control of die-cast parts runs through the entire production process. The three key links—mold design, die-casting technology, and post-processing—are closely interconnected, and deviations in any link may lead to product defects.

Mold design serves as the "innate foundation" for the quality of die-cast parts. The dimensional accuracy of the mold cavity directly determines the dimensional tolerance of the product. Failure to reserve a reasonable shrinkage allowance during the design phase can easily result in dimensional deviations. The design of the runner and venting system is particularly critical: an unreasonable runner will cause uneven filling of the molten metal, leading to cold shut defects, while poor venting will trap gas inside the cavity, forming air holes. In addition, uneven distribution of the mold cooling system will cause differences in cooling rates across different parts of the casting, resulting in deformation or shrinkage cavities. High-quality molds require optimizing the cooling path based on the casting structure to ensure a uniform temperature field.

The setting of die-casting process parameters is the "core key" to quality control. The injection speed and pressure must be accurately matched: low injection speed can easily lead to insufficient fluidity of the molten metal, causing incomplete casting; improper control of high injection speed, on the other hand, may result in splashing and gas entrapment. Mold temperature is also crucial: excessively low temperature will cause the molten metal to solidify rapidly, affecting forming quality; excessively high temperature will prolong the forming cycle and may even lead to casting sticking to the mold. Meanwhile, the melting temperature and composition ratio of the alloy liquid must be strictly controlled—excessive impurities or improper temperature will reduce the mechanical properties of the casting and increase the risk of cracking.

The post-processing link is the "final line of defense" for improving quality. The deburring process can eliminate sharp edges and prevent scratches on components during assembly; surface treatments such as spraying and electroplating can enhance the corrosion resistance of castings and extend their service life; for products requiring high precision, CNC machining is also needed to correct dimensional deviations and ensure compliance with assembly standards. If post-processing is not in place, even if the previous processes meet the standards, the final service performance of the product may be affected.